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Although Bangladesh has suffered from different types of floods which have caused enormous damage to properties and lives, managing floods still remains a challenging task. Flood management is a multisectoral activity due to its complexity, scale, and multidisciplinary nature. Sirajganj district can be regarded as one of the most vulnerable areas in Bangladesh and hence a study was carried out for Sirajganj district to provide guidelines to combat challenges to flood risk management. The flood frequency analyses at three river stations using water level data were carried out, the flood inundation map for different return periods and a flood depth versus damage curve are plotted to address the vulnerable areas and damages, and to help design flood mitigation structures. It can be inferred that damages will be proportional to return period since the risk is a function of hazard, vulnerability, and exposure. Both structural and non‐structural measures including rejuvenation of the Jamuna River and low‐cost flood resistant building approaches for flood affected char (island) people are suggested along with a few recommendations to mitigate floods in the study area. The government, Non governmental organization (NGO), funding agencies, and transboundary countries should come forward to mitigate flood hazards to improve the livelihood of the affected people.

A multi‐model ensemble provides useful information about the uncertainty of the future changes of climate. High‐emission scenarios using representative concentration pathways (RCP8.5) of the Fifth Phase Coupled Model Inter‐comparison Project (CMIP5) in the Intergovernmental Panel on Climate Change (IPCC) also aids to capture the possible extremity of the climate change. Using the CMIP5 regional climate modelling predictions, this study analyses the distribution of the temperature and precipitation in Bangladesh in the recent years (1971–2000) and in three future periods (2010–2040, 2041–2070 and 2070–2100) considering RCP8.5 scenarios. Climate changes are expressed in terms of 30‐year return values of annual near‐surface temperature and 24‐h precipitation amounts. At the end of the century, the mean temperature increase over Bangladesh among the 11 RCMs will vary from 5.77 to 3.24 °C. Spatial analysis of the 11 RCMs exhibited that the southwest and the south central parts of Bangladesh will experience a greater temperature rise in the future. Possible changes in rainfall are also exhibited both temporally and spatially. Based on the analysis of all the RCMs, a significant increase of rainfall in the pre‐ and post‐monsoon period is observed. It is also evident that monsoon rainfall will not increase in comparison with pre‐monsoon season. Zonal statistics of 64 districts of Bangladesh are also conducted for the 2020s, 2050s and 2080s to find out the most exposed regions in terms of the highest rise in temperature and changes in precipitation.

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